Ten years ago a supermarket was built at the bottom of my garden. There were supposed to be no deliveries before seven in the morning and after eight at night, but they’ve started delivering earlier and later and on bank holidays. We complained to the planning department, who said they would get three warnings before being fined. However the supermarket soon went back to its old ways, and as I write a delivery is taking place at 10pm.
The answer is to keep on to the planning department to enforce the conditions which were evidently attached to planning consent for the site. Keep a diary of the comings and goings at the supermarket and submit your notes to the planners at regular intervals. You could possibly take the supermarket to court yourself for “nuisance”, but getting the local authority to take action is your best bet.